SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '69aa620439efd9a31b5d2555272ef4cacd254e59f232f12a86ac5e3d41ae91ba' 
  AND token = 'nedtZFpMPBt77MBRNLxy4BFxLIpxjjPRlRKBhpPgPzg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}