SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27ff7aa1ad7d5f899e6c0784c722515c91a9a2310c783ace8a8a9798b326a96d' 
  AND token = 'Haax0d8H+WuUNCqmaA60TALpNhYBj9ZfXDX9CiDY5aM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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