SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee9e18743f55622759c9b58831e9da400b7be3f9df7f577f9f8825c5a6200c7a' 
  AND token = '+BGKWdyfYKTNe/Jf4+Dk+FTg/ZCk1IpzM3GfzAaqjLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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