SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '87bac2b086cf1e8f24cd942001f630ffcf792177cf374e64349a5ef6de5b701f' 
  AND token = 'nmnXMvbEXhTFuUBstNP4YYGpwYyp9UjXjK89gGQQ2Fo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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