SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '199c202cb526d0223816aa7a848e7a73541d590937019bd8147bf93f6057a277' 
  AND token = 'XwYA/BSZfK3e2HKJGSrmlnwpwZQW88ZXlfab6BMg+Ko=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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