SELECT 
  1 
FROM 
  vi_lock_keys 
WHERE 
  key_id = '9a6678f9bf0632d5700dd1b8e150c3b399b1457a601fd26c1ab2c9c617fbb71c' 
  AND token = 'RRKEMohn8IamQw+XrWj35VXcplZt/uQqNz4A3heXx60=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}