SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '523b71a5e8defe1538c475fa72db1c6150bf7437b6a0777ca86633c697335bc2' 
  AND token = 'uYT0ndsh3Fuv7XBxkqNHeJyVfbgvWD8PEJTFlOdC0fM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}