SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '735e248ba5b5650bc1b2cd08e596947929a0c37d228549cfce46b9836f79e7a6' 
  AND token = 'r2iKF6DlKP4/bRo784dqm0iUPJ4VgnzqZ599qaBs+Wg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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