SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf60e4624afca9266454f9832d723ce9b63f6bf9fbc57062c2700fa6e3035a5a' 
  AND token = 'eRsF3wqX+ddduUdadk5jW5ncSeo1Ge0bgSLPP7LUZkI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00059

JSON explain

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