SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8fa1606ccd28f6cd205f5896ffa1c5df1c111a0435c42a4b63fe45c99be645bf' 
  AND token = '12FnpkqXVx2sUps7UBrX4HBAQihUWW90feeWcJaSUEw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00065

JSON explain

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