SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '68482dccf098e04b520b58710559ff5fb898662128512eeff106d3f3793f733d' 
  AND token = 'FjxnT0jgfpJ02GgJ9aOZ+/VxIbAVP5Vpu9LqrqueZ9g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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