SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0ace2a3d090107e38bcf3c92ce68ed02d6e221be8708b323aafa0b6bfa5a5544' 
  AND token = 'F90gumOXZbv4oOSKwD2aVHSHLy1CR/SCX6tOuRMkaiU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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