SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8efada78e271765f33ded314ac697e202c7c690007f89694d0df64f517714850' 
  AND token = 'nPAF6vjpuPRPZyXQQV9g3HFlxxUzezvmWhollM51zIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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