SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbac8cdb63f418d435ab8cdf9b4709f17aa5cf03e113bd85c6895259893902a8' 
  AND token = 'uZclOOXr6oy8AmHUVfgElYwKiX5Y/sUD286jBbcKdHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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