SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0f434bc1310e47384920a3c320a31fadd933a1a48d52f8bd8bd5f3b208dcd4bf' 
  AND token = 'LDY84Vkwd5sAqeu1qCKX2O3rIpGfiF5HgOBorRvlXic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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