SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dbb9bcca364930a35a439ab877befd13108b3470f3d46a03554de38e69287c10' 
  AND token = 'BIInEpZDaQDVVXTKYX8wBH8TgJmMk1Cvn9m2D3pRRBA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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