SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '977f75f7b9630385eb20ca029ddafb409e061802e2a1d47cb3a5acf6d09c02f0' 
  AND token = 'uPQlgRq3R4SIPpto+6rAffX4Dq7zhRnwkVB/3G6wRsY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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