SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '367185cdd0edf7ee15d17271b1972ccc132bba4cb0cd43f42964d1e966723dd7' 
  AND token = 'U8gzr4HkdaCQ49+U5MH3+hxGPmgxEBq846sk0o/jdqk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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