SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e0b9958b1770143daf5890443ab251226e0847c99c73a50e5cbd6c043cea5b1' 
  AND token = 'KOOrj5qocib5XSqfymv+vQFFucIALD+6heT872fP9t4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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