SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'deb201bf417ad18ed22116f02336f2830bbfcbc03c746824df0a9ac16bcd0dc0' 
  AND token = '1A13I0YzGQ0ANLlZ1fFdyu2VslPHYxfU9Ygf+0y2Q14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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