SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '70fc30eccba113968dad9869b0bdfe0070c04343f73952049ac130e6ab2842d6' 
  AND token = '4mTzFpzke6Hm522RmqqILQVQFyQ+ljHsv5rWPkY986w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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