SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a477f6af3658b5cf8487385bf151f111a6ef99de8e9c3e679122a26f41702240' 
  AND token = 'JyJVMVXpMkIDaR13dYv7FBKVQ08JGWFfh0O/CbQvsjk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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