SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0f674694391738264356b3ac3c58c316b7105af762f04504586a3f074328a15' 
  AND token = '8Px3zr1GzYZ/25qLRjEVLU580TSpH4n8kNG3LlD9rNU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}