SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ede1dcc97f456a146ad55038f0982eebd14d97af01637eb00d67c48e865af59a' 
  AND token = '0McKjJArr+K7WTT0NvU6qVAIVFjANUoOwX9IUytp0U8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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