SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0156e165b39396484fd2e772d3556303d5b0c53700c6964269dae16cbd37328' 
  AND token = '5oM95BoxpF6NEpP1q2K9Una4Cw1dUCTgzwLZbon3VlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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