SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69170dc3ddc86b14056d7f4c4c199e04d70b0d3a8a805c63b2ada46f4996243f' 
  AND token = 'BUqlc8ngGcRrgcM0pVRtQVMLcGDsELAILPaiSUpbTz4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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