SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f6962d9cbb570c4a1c74b8ea296bc52ef311d80fd772bb4479e6867b3a62ea3c' 
  AND token = 'x5X4OfqIRgmc8cAgP9Ywew/vOnsujngqz5hgpPSHX9M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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