SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f94b6347c176d062921a2e51018db625d245cbdbfc2341409451a4557dc46af' 
  AND token = 'h874TGDuJcTHDnYbtetN45aTMD6ZRYuakA7R7fQUrBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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