SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89851afa834f8a5a000e86ed3590fce311f9e287fc81f637aeb2e7c60b9bdf43' 
  AND token = 'ez9NXUJ8O441W+GKUdT6qlqOGFohRFUkAmUKEQrfuuc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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