SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96465175c0cb8f8c95de4641d1744c636541d255676d474923e9262adc2d9787' 
  AND token = 'NgwQf3CTSxAHkBz/Endq+ggbpW4C2ysLG7LCHZvnMX0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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