SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7dfb413af96bc2e6513196ca5d996d465d16f94ebe74a989f783b6b74e6141cf' 
  AND token = 'RRIFQJ/zNM26bxUjKe4sBAD8CKAldR11QDN/9dXRLLM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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