SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2e2224a2d0a9e6852d6df1ea48bbeac5c0ce81accd82157d2fe7ed7edf7ec9c' 
  AND token = 'CcSfLJQra+vML3JOaHoUZnsu8TLts9ofChkCFIDNuyw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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