SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d265377d3a952632e760f9c00cee431c7fe70d0d67230453c5090a6cd28318d' 
  AND token = 'PgMBCmZrhCM+bhZlBZIgml8/ft4v8+4J6ZA5glP41pY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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