SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '565cb7e9f381ef389face31208434617c3a626e89179a9f8a98f285ed3fe4b18' 
  AND token = 'R64vS6/jbmypB6YqsABtxhUpP2kL3COU2ZJQbSPEdMU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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