SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '668a4cd4c9dde7e58f6c473f55213fe60b14cb4bac5b644264066ba79de2d088' 
  AND token = 'aYU5g4Vo0XvCRzbOOiZeGmXFkBxoO04uzDXSQt6LrP0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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