SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f9f714dc609f2a7a798acf95a9b5e5a32ebc42c23a0591de312ffa7f8839c906' 
  AND token = 'AP3VCx1j6vCKlZlBS9yJjoG42ZVacu0hA6+wpiAI/L8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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