SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '37ca2327c3a1846e847caa2a61d77485246793952bf0f5df8574a412315b8d42' 
  AND token = 'tumOS2yc7cJ39Ha5+oNmiSA65aVpkpcIaId5Z4CFcZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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