SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c63aedd8170364dd38085dfc668415349b9ba5362f7df77479e164538bdd19a' 
  AND token = 'YXYC+dFJ1v8NOozLR44SV+lHvBSE1HlWIWcDgHQ4JuA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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