SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e9df205fbe595f572798fbfbd40f72853f34b7b7aa592a86dd8786f93d565910' 
  AND token = 'smHISTU2JYZ11EuIv+t8adjWySrkrqfyVfAujGXWPTo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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