SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87f1ae9ecd9ee015420637f44345f22aa389e45a6070197cbd617b689325be7c' 
  AND token = 'q4TUFSGLzwUaRlDI9MZD5CU2FsNqkZ6Sc9g4cdwvsdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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