SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1716b682d23a800ca6b76147717d7f7025ae229423c6cb05a991b39910eb3d94' 
  AND token = '8gADFBnvFKAIWKVWa/L1X2+BB7OUZmoWiK4BJt+Z/5E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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