SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd8cfc3643591436e2f796afdc77fd0c357451bfe92f854bdcc49b04c07e628ff' 
  AND token = 'DClrvF6yR5SEGYrthBwmrbzdHGDJbPBoa5XcMJlELdk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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