SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'efa47958f6728be1c8e55d2b308afee9e993845dd47d82b5d06b3717a155647b' 
  AND token = 'RZ2NFnTgvHT9qg6/2dhqvZG2sUl49j4FIkaNwbX63BA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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