SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c2be4685b67480a2d28c9bc3ea7ccc9daae6c4e1a5a945c13b8a718f0a14a4e' 
  AND token = 'H8CIPz7SPu4g2nttdqu6dcfcG11+aKudpqkBxjPk8HM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00098

JSON explain

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