SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4be5dc08c0c525332c78de6f81810c41dfd5f3949e32b14a04e6cf893796b585' 
  AND token = 'ealwhiHey2xQfbPGUqhfn9eRlMUKGFIpyYoppKxfs9A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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