SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '955d2fd81120660084b7b2b23b7ef0368b0a92e24164d2ca0205c70a00cc5a29' 
  AND token = 'CRYBFtbG4QAnUWNGkMmIfDRwyVCw+Afd5Iu9Pcz1sQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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