SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49314356bf6b0748ce90f0f2bf942cbf9398edf4988cb8a2da0b684c46b45002' 
  AND token = 'uwH+Ah2cEd4iR/J0SF30J4t3YTQS73tkKzPs5z1xXpw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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