SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97d6b70527b11ed6d2a044027b0f935c13b5069f4446e16889be4b47fee254d7' 
  AND token = '7w7WuKz8uMLW6WjY8SnZ8yoDvGAxsRCxkqJA9PtrZhc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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