SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0de8ee50987bb7722df7959829541d3c36f78eb26ae8062454c1b7909e47d5b7' 
  AND token = 'SiOOOtjmD4/sIVfnuJcjgRJQeNX2aBX5BkYQMhGwi1U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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