SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '609aed89c832ac9dfa25ece3f1c07408d23ab1609d35e7e16f8999647cfbfe09' 
  AND token = 'vCHFE3EOPBsWM8WH6MYkMLrFTpQb1E/SGGZFYxZJobM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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