SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e652592e4b0ba4b6a22ff30363277c910ad8ba03798efde48b2943a10e84bd1a' 
  AND token = 'XxySUAIkKa41mIVitPrJoHlM7s3Kz2yiQ5XPbL2mHpw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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