SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f070940501e907805a1946a23421fc3e6970972ad228d03e9c6b2516b4800ca4' 
  AND token = '7J23YM/TxoMv+VRQMdK2eqWFfdyOxOd/t4RRFNsDu/4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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