SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a007cc7fe5818dc71f1c23350733a06c620c9535b7c97212b4974ca19e4b840e' 
  AND token = 'F1OMxxW76EbSuBmCC1AHqvd0q5YZXsWaSgSw6YfrOjY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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