SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23106cffded35829eb10df6c2fad69552d2a6cb3d12e1e86a0faacb5dce142f6' 
  AND token = 'qcxNx/Q5gBwndz1Fc2dv5iLPnqAGOa/wb74mJukBdDU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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