SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c33ca25a46bfef21b9f0ba919177228078893e4d1797abb73fa369bfa3aeff45' 
  AND token = 'XWYyFsvIBpOXTEl0ebYWhDcrmwehQ3qz4jn2BLim7RQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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