SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9b30af291d0576da309dabcb33eaad0c2aa93af608b1e4dda948f311bd2c8e9' 
  AND token = '5y7goBQgCqX5XXHe1M53N/LKDeDpXAOiRjos/XpC/eg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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