SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '51cac71472ad9ae2a42f286335294967eea6bde033ee2652d53ac8f845a5d6bd' 
  AND token = 'hpWSV8Pdtu/eSji5A862BzOB44hgoGVcCKvOjdgXZJ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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