SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60fe1862dc12a4c709c7a7f2677beb34d397738bac268e426bd8815c83f0b15b' 
  AND token = '20rRmyYeuqev4GIZJKx7P+GYH88B3X+52qWGxfhYkLM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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